Field of the Invention
The present invention relates to a display device, and more particularly, to an organic light emitting display device having slim profile and flexibility, and a method of manufacturing the same.
Discussion of the Related Art
Flat display devices include a liquid crystal display device (LCD), an organic light emitting diode (OLED) device, a plasma display panel (PDP) device, a quantum dot display device, a field emission display (FED) device, an electrophoretic display (EPD) device, etc. Each of these flat display devices typically includes a flat display panel for displaying an image in which a pair of transparent insulating substrates facing each other are bonded to each other, with an intrinsic light emitting layer, a polarizing layer or other optical material layers interposed therebetween.
As the demand for a flat display element having a small space occupation is increasing in accordance with the recent trend of large-sized display devices, an organic light emitting display device is considered as the next generation display device among these flat display devices. This is because the organic light emitting display device typically does not require a separate light source and a structure to assemble the light source to a display panel, and includes organic light emitting diodes spontaneously emitting light in the unit of pixels.
An organic light emitting diode typically comprises an anode, a cathode and an organic layer between the anode and the cathode. The organic light emitting diode emits light when pairs of electrons and holes, which are injected into the organic layer between an electron injection electrode (a cathode) and a hole injection electrode (an anode) and then are recombined in the organic layer, are transitioned from an excited state to a ground state.
Meanwhile, a touch panel, which can recognize a touch point contacted by a human hand or other input unit, is recently added and attached to an external surface of a display device.
Touch panels are divided into a resistive type, a capacitive type, and an infrared sensing type. Presently, the capacitive type touch panel is advantageous for small-sized display devices due to ease of fabrication and sensitivity.
Hereinafter, a conventional organic light emitting display device to which a touch panel is attached will be described with reference to the accompanying drawings.
FIG. 1 is a cross-sectional view illustrating a conventional organic light emitting display device to which a touch panel is attached.
As shown in FIG. 1, the conventional organic light emitting display device includes an organic light emitting display panel 10, a touch panel 20 and a cover film 30 which are sequentially stacked. First and second adhesive layers 15 and 25 are provided between the light emitting display panel 10 and the touch panel 20 and between the touch panel 20 and the cover film 30, respectively.
Herein, the organic light emitting display panel 10 includes a substrate, a thin film transistor array arranged on the substrate in a matrix, and organic light emitting diodes connected to respective thin film transistors of the thin film transistor array. An encapsulating substrate sealing the organic emitting diodes and a polarizing layer are further provided. In this case, the first adhesive layer 15 is disposed on the polarizing layer. The touch panel 20 includes a plurality of touch electrodes disposed on its touch substrate for detecting a user's touch.
The substrate of the organic light emitting display panel 10, the encapsulating substrate, the touch substrate of the touch panel 20 and the cover film 30 are typically formed of a hard material such as glass. These substrates typically have a thickness of about 0.5 mm or more, and thus, it may be difficult to manufacture an organic light emitting display device to which a touch panel is attached with slim profile and desired flexibility.